navigation and vessel inspection circular no.8 9'3

U.S. Department~of Transportation !

United StatesCoasi Guard

CommandantU.S. Coast Guard

2100 Second Street SWWashington, DC 20593-0001Staff Symbol: G-MTH-4Phone: 202-267-2997

COMDTPUB P16700.4NVIC 8- 93 . '!l

12 November 1993

a b c d e f g h i j k I m n 0 p q r s t u v w x y z

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NAVIGATION AND VESSEL INSPECTION CIRCULAR NO.8" 9 '3Subj: EQUIVALENT ALTERNATIVES TO 46 CFR SUBCHAPTER H

REQUIREMENTS RELATED TO MEANS OF ESCAPE, SAFE REFUGEAREAS, AND MAIN VERTICAL ZONE LENGTH.

1. PURPOSE. The purpose of this Circular is to provideequivalent alternatives to existing requirements for means ofegress, safe refuge areas, and limitation of main verticalzone (MVZ) length for certain passenger vessels required tomeet the structural fire protection requirements of 46 CFRSubchapter H. The policies in enclosure (1) update thosepreviously published in NVIC 14-91. Enclosure (2) providesequivalent alternatives to 46 CFR Subchapter H limitations onthe mean length of MVZ's.

a. The alternatives in enclosures (1) and (2) are applicableonly to vessels which:

(1) Do not operate on international voyages subject toSOLAS;

(2) Have no overnight passenger accommodations; and

(3) Are comprised predominantly of large public spaceswhich generally encompass the entire length andbreadth of each main vertical zone.

b. In addition to the above, the guidance in enclosure (1)is only applicable to vessels which:

(1) Are certificated under Subchapter T or H; and

(2) Operate in protected or partially protected waters.DISTRIBUTION - SDL No. 131

A

B

CD

E

F

GH

NON-STANDARD DISTRIBUTION: (See page 5.)

NAVIGATION AND VESSEL INSPECTION CIRCULAR NO. S-' 9'3

"Protected waters" means sheltered waters presenting nospecial hazards such as most rivers, harbors, lakes, etc.

"Partially protected waters" means: (1) Waters within 20nautical miles of the mouth of a harbor of safe refuge,unless determined by the Officer in Charge, MarineInspection (OCMI) to be exposed waters; and (2) Thoseportions of rivers, harbors, lakes, etc. which the OCMIdetermines not to be sheltered.

c. In addition to the above, the guidance in enclosure (2)is only applicable to vessels which:

(1) Are certificated under Subchapter H, or arecertificated under Subchapter T and comply with therequirements of Subchapters F and J for thosesystems required by this enclosure; and

(2) Operate only on waters determined by the cognizantOCMI to be Qrotected waters.

[NOTE: The guidance in both enclosures may not be applied tovehicle ferries. It may be applied to non-vehicleferries which meet the above criteria.]

2. DIRECTIVES AFFECTED. NVIC 14-91, dated 2 October 1991, iscancelled. The applicability of Commandant (G-MTH) PolicyFile Memorandum 3-89, "Draft Stop Requirements for 46 CFRSubchapter T Vessels," is cancelled for all vessels to whichthe alternatives offered in this NVIC are applied.

3. BACKGROUND.

a. Coast Guard fire protection regulations have beendeveloped over the years primarily based upon passengerships which operate in ocean service. The passengerdensities of these vessels are relatively low since theytraditionally provide overnight accommodation spaces forall persons on board. The requirements of 46 CFR 72.05-20are based on the philosophy that all passengers in eachMVZ should be provided with a direct, protected means ofegress to the embarkation deck via stairtowers.Stairtowers provide avenues of egress which protectpassengers from the hazards of fire, smoke and exposure toweather. Further, stairtowers provide direct access tothe embarkation deck so that passengers can proceed toprimary lifesaving equipment without exiting a protectedspace, should this become necessary.

b. There is an increasing public demand for dinner excursionand gambling trade vessels which have large publicspaces, no overnight passenger accommodations, and

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NAVIGATION AND VESSEL INSPECTION CIRCULAR No.8- 93

operate close to land. These vessels have much higherpassenger densities than those envisioned whenSubchapter H was developed. The size and configurationof many of these vessels do not easily permit theincorporation of certain Subchapter H designrequirements. Since weather hazards encountered inprotected and partially protected waters are less severethan those encountered in ocean routes, it is appropriateto permit weather deck egress, if fire safety is notjeopardized. However, it is inappropriate to assume thata vessel will be capable of returning to shore todischarge passengers in sufficient time to avoid a majorcasualty in the event of a shipboard fire. Thus, it isimperative that these vessels be capable of serving astheir own rescue platform with properly designed egressand safe refuge systems, structural fire protection, andfire protection equipment.

4. DISCUSSION.

a. This publication is primarily oriented towards thetechnical aspects of ship design and is intended to beused by architects, engineers and Marine Safety Centerpersonnel, and to a lesser extent by the cognizantOfficer in Charge, Marine Inspection.

b. Designers employing the alternatives in this NVIC shouldbecome familiar with the content of related Coast Guardpolicies including the following:

(1) NVIC 6-72, "Guide to Fixed Fire-Fighting EquipmentAboard Merchant Vessels";

(2) NVIC 6-80, "Guide to Structural Fire ProtectionAboard Merchant Vessels";

(3) COMDT (G-MTH) Policy File Memorandum (PFM) No. 1-93,"Fire Protection Relating to Elevators";

(4) NVIC 10-93, "Guidance to the Acceptance of NFPA 13for Automatic Sprinkler Design, Installation andMaintenance"; and

(5) NVIC 16-91, "Special Fire Protection Systems forAtriums."

c. The alternatives outlined in this NVIC make use oftechnological advancements made in fire safety sincepromulgation of Subchapter H. Incorporation of activefire safety systems, coupled with route restrictions anddesign and performance standards for emergency egress andrefuge systems, permit the acceptance of alternative

3

NAVIGATION AND VESSEL INSPECTION CIRCULAR NO. 8- 93

designs which provide a level of safety equivalent tothat established in existing regulations. The guidancein enclosures (1) and (2) is based on a modified landbased flow criterion that recognizes the dynamics ofpeople movement to areas of refuge through restrictedopenings. The underlying safety philosophies upon whichthis guidance is based call for vessel designs whichincorporate a balanced approach to life safety. Thisbalance is achieved through the use of passive and activesafety features and equipment which address safetyconcerns involving passenger capacity and distribution,fire prevention, provision of adequate means of egressand on board qualified refuge areas, fire and smokecontrol and containment, and fire suppression.

d. Enclosure (3) provides definitions for terms used inenclosures (1) and (2).

5. IMPLEMENTATION.

a. Vessels to which enclosures (1) and/or (2) apply may bedesigned to the applicable requirements of Subchapter Hor Subchapter H as modified p~ the alternatives describedin the enclosures. Vessel owners electing to employ thealternatives outlined in this NVIC must do so in allareas. The alternatives may not be applied in apiecemeal fashion. As always, the Coast Guard willconsider other designs, arrangements and equipment whichare demonstrated to provide an equivalent level ofsafety. This includes alternatives that incorporatestate-of-the-art lifesaving equipment (i.e., evacuationslides, inflatable liferafts, etc.) subject to theconcurrence of the OCMI in whose area the vessel will beoperating.

b. Certain vessels incorporating the alternatives providedin enclosures (1) and/or (2) will require the use of oneor more advanced fire safety systems such as automaticsprinklers, smoke extraction systems, targeted emergencyannouncement systems, etc. Plans related to thesesystems are particularly good candidates for submissionto the Marine Safety Center under the provisions of NVIC10-92, "Coast Guard Recognition of Professional EngineerCertification of Compliance with Coast GuardRegulations."

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NAVIGATION AND VESSEL INSPECTION CIRCULAR NO. 8- 93

c. Officers in Charge, Marine Inspection are encouraged tobring this NVIC to the attention of appropriateindividuals in the marine industry within their zones.

c.~.A. E. HENNRear Admiral, U.S. Coast GuardChief, Office of Marine Safety,

Security and Environmental Protection

Encl: (1) Guidance on Means of Egress and Refuge Areas forCertain Passenger Vessels Operating in Protected orPartially Protected Waters

(2) Equivalent Alternatives to 46 CFR 72.05 Requirementsfor Limitation of the Mean Length of Main VerticalZones

(3) Definitions of Terms Used in Enclosures (1) and (2)

Non-Standard Distribution:

C:e New Orleans (90); Hampton Roads (50); Baltimore (45); SanFrancisco (40); Philadelphia, Port Arthur, Honolulu, PugetSound (35); Miami, Houston, Mobile, Long Beach, Morgan City,Portland OR (25); Jacksonville (20); Boston, Portland ME,Charleston, Galveston, Anchorage (15); Cleveland (12);Louisville, Memphis, Paducah, Pittsburgh, St. Louis,Savannah, San Juan, Tampa, Buffalo, Chicago, Detroit,Duluth, Milwaukee, San Diego, Juneau, Valdez (10);Providence, Huntington, Wilmington, Corpus Christi, Toledo,Guam (5).

C:m New York (70); St. Ignace (5); Sturgeon Bay (4).

D:d Except Baltimore and Moriches.

D:l CG Liaison Officer MILSEALIFTCOMD (Code N-7CG), CG LiaisonOfficer RSPA (DHM-22), CG Liaison Officer MARAD (MAR-742),CG Liaison Officer JUSMAGPHIL, CG Liaison Officer WorldMaritime University, CG Liaison Officer ABS (1).

ABS (260).Det Norske Veritas (1).NOAA Fleet Inspection Officer (1).U.S. Merchant Marine Academy (1).

5

Enclosure (I) to NVIC 8 -. 9.3

Guidance on Means of Egress and Refuge Areasfor Certain Passenger Vessels

Operating in Protected or Partially Protected Waters

GENERAL

1. In lieu of full compliance with certain Subchapter Hstructural fire protection requirements, vessels to whichthis enclosure applies may be designed to Subchapter H asmodified by the equivalent alternatives contained herein.

2. This enclosure provides guidance for determining the maximumnumber of persons (passengers and crew) that may be assumedto occupy various spaces. Once maximum capacities have beendetermined, egress components (i.e., stairtowers, stairways,landing areas, doors, corridors, etc.) may be sized. Thisguidance is based on a modified land-based flow criterionthat recognizes the dynamics of people movement to areas ofrefuge through restricted openings.

3. The equivalent means of egress alternatives described hereinrequire that each MVZ be served by at least one stairtower.The remaining egress components needed to fulfill therequired 100% egress capacity for each space may be providedby stairways directly accessing qualified refuge areas, doorsthat lead directly to weather egress systems and/or doors inMVZ bulkheads directly accessing qualified refuge areas.Some restrictions apply, as described later in thisenclosure. No other exits may be considered to contribute tothe required means of egress capacity. Stairtowers andstairways must be sized to accommodate the number of personsexpected to occupy spaces or areas on a deck-by-deck basis.Stairtowers and stairways serving multi-deck spaces requirespecial treatment, see paragraph 17. A continuous protectedavenue of egress must also be provided from qualified refugeareas to an embarkation area. See paragraphs 18 and 19,below.

4. A qualified refuge area must be provided for all passengersand crew to protect them from the effects of fire. Therequirements for qualified refuge areas vary depending onvessel size and arrangement. In general, qualified refugeareas must be properly sized, protectively bounded, andprovide protected access to the embarkation area. Spacesadjacent to qualified refuge areas may require an automaticsprinkler system or other appropriate fire suppressionsystem. See Tables 1 and 2.

Enclosure (1) to NVIC 8 -- 9

5. The crew plays an essential role in any shipboard emergency.During an evacuation, they must react swiftly to controlpassenger movement and direct them to refuge areas. AnEmergency Evacuation Plan (EEP) is required for each vesseldesigned using the alternatives described in this NVIC. Eachmember of the crew must be required to become familiar withthe content of the EEP and the actions they should take inthe event of a shipboard fire.

DETERMINATION OF MAXIMUM NUMBER OF PERSONS PERMITTED

6. The maximum number of persons (passengers and crew) permittedon a vessel, and the maximum number of persons considered tooccupy the various spaces for the purpose of sizing egresscomponents, shall be determined as indicated below.

7. The calculated total number of persons permitted on board mayinclude persons on weather decks. However, if this is done,the OCMI, in cooperation with the operator/owner, shoulddetermine the extent of seasonally cold or otherwiseinclement weather during which the weather decks becomeunsuitable for the carriage of passengers, when vesselactivities are generally confined to interior spaces. Inthese cases, the OCMI should endorse the Certificate ofInspection (Cal) to limit the total number of persons allowedon board during these periods to the number for whichinterior spaces were designed. For example, a casino vesselwith a total capacity of 800 persons, of which 200 areaccounted for by weather deck seating and deck area, wouldhave its Cal endorsed for the carriage of a total of 600during seasonally cold/inclement months. Specialconsideration may be given for a vessel normally engaged incasino service if, on occasion, it provides ferry service toand from a special event. In such cases, it is possible thatthe vessel will be loaded to capacity and that passengerswill be carried on open decks in inclement weather. Theabove provisions for limitation of passenger capacity duringseasonally cold, inclement months are intended to limitpassenger capacity only when the nature of the vessel'sservice is such that passenger activities are generallyconfined to interior spaces. In all cases, owners andoperators of vessels with egress and refuge system designsreliant on weather deck egress routes and qualified weatherdeck refuge areas must ensure these areas are kept clear ofice and snow whenever passengers are on board.

8. In spaces such as lounges, club rooms, casinos, diningfacilities with non-fixed seating, and other similar spacesdesignated for passenger use (including weather decks), themaximum number of persons permitted is the greater of thatpermitted by the deck area criterion or fixed seatingcriterion described below. Where appropriate, the twocriteria may be combined within a given space to determine

2

Enclosure (1) to NVIC B- 93

the total number of persons considered to occupy the space.(See paragraph 12 below concerning stability considerations.)

a. Deck Area Criterion. One person may be permitted for2 2every 0.93 m (10 ft ) of gross deck area.

[NOTE: 2 2The 0.93 m jperson (10 ft jperson) gross area "rule"is used to simplify, in the early design stage, thedetermination of the maximum number of persons thatmay be carried and the sizing of egress componentsand refuge areas. To ensure that the available (net)deck area is not excessively reduced after accountingfor slot machines, tables, loose chairs and otherroom furnishin~s, a minimum net deck area of 0.65m2 jperson (7 ft j person) must be provided. It isappropriate for the cognizant OeMI to further limitthe number of persons permitted, if the percenta~e offurnishings is such that less than 0.65 m2 (7 ft )net deck area is provided for each person in a givenspace. The Marine Safety Center should be consultedin such cases.]

In computing gross deck area, areas occupied by thefollowing must be excluded:

(1) Obstructions, including stairway and elevatorenclosures, elevated stages, bars, cashier stands,etc., but not including slot machines, tables orother room furnishings;

(2) Areas for which the number of persons permitted isdetermined using the fixed seating criterion;

(3) Toilets and washrooms;

(4) Interior passageways less than 86 cm (34 in) wideand passageways on open deck less than 72 cm(28 in) wide;

(5) Spaces necessary for handling lifesaving equipment,anchor handling equipment or line handling gear, orin way of sail booms or running rigging; and

(6) Bow pulpits, swimming platforms and areas which donot have a solid deck such as netting on multi-hullvessels.

b. Fixed Seating Criterion. One person may be permitted foreach fixed chair or 46 cm (18 inches) of width of fixedbench seating provided.

9. For determining the maximum number of persons on board, crewshould be assumed to be occupying public and service spaces.Crew spaces include; working spaces, crew lounges, and may be

3

Enclosure (1) to NVIC 8

sized based on their normal operating capacity. If crewsleeping spaces are provided, means of egress from thesespaces must be sized for their full capacity.

QUALIFIED REFUGE AREAS (QRA)

10. Qualified refuge areas must be provided for all persons onboard. Standards for on board qualified refuge areas differdepending on vessel size and arrangement. In the event offire, complete evacuation of the fire affected MVZ ispreferred. A greater degree of protection must be providedfor qualified refuge areas which are located within a fireaffected MVZ. When designing qualified refuge areas andStage I and II Egress routes, it is necessary to considerthe possibility that a fire may originate in any space(other than those which pose no fire risk, such as voids,cofferdams, tanks, etc.). The fire safety measures requiredby this NVIC are intended to ensure that a fire will becontained in the space of origin, which may be assumed forthe purposes of design. Each fire scenario must be examinedto ensure that egress routes and qualified refuge areas areavailable under any circumstance.

11. Standards for qualified internal and weather deck refugeareas are outlined in Tables 1 and 2 of this enclosure,respectively. In cases where Tables 1 and 2 do not indicatea standard for a specific fire division, the requirements ofSubchapter H apply. The maximum number of persons assumedto occupy qualified refuge areas shall be determined usingthe guidelines provided under "Determination of MaximumNumber of Persons Permitted," except that when applying thedeck area criterion, one person may be permitted in the

2 2refuge area for every 0.47 m (5 ft ) of gross deck area.

STABILITY CONSIDERATIONS

12. The maximum number of persons permitted as determined usingthe criteria outlined in this enclosure may be furtherlimited by stability considerations, or by the cognizantOCMI. Stability calculations submitted to the Marine SafetyCenter for approval must include the various possibledistributions of passengers and crew at qualified refugeareas and any anticipated egress scenarios which may occurduring an emergency evacuation, if these conditions presentthe worst case with respect to vessel stability. Dueconsideration must be given to asymmetrical egressarrangements which could result in passenger crowding to oneside of the vessel.

4

Enclosure (1) to NVIC 8- 93

STAGE I EGRESS - EVACUATION OF THE SPACE OF FIRE ORIGIN ANDMOVEMENT TO QUALIFIED REFUGE AREAS

13. The ability to rapidly evacuate a space where a fire hasoriginated is central to the safety of passengers and crew.Thus, multiple, properly sized means of egress must beprovided. Designs must permit evacuation of passengers andcrew out of immediate danger, and enable all affectedpersons to move to pre-designated "qualified refuge areas"where they can be protected from the fire. This first stageof passenger and crew movement is referred to as Stage IEgress. Stage I Egress routes are designed to permitinitial evacuation of the fire affected space and movementto refuge areas in a matter of minutes, before the firedevelops to the point that the integrity of bulkheads andwindows is seriously threatened. The minimum "two means ofescape" requirements contained in 46 CFR 72.10 remainapplicable.

14. Stage I Egress routes should be widely separated, marked asrequired by 46 CFR Subchapter H, and be directly accessedfrom public spaces by "simple modes." Simple modes includepassage through a single set of exit doors or stairtowerdoors as follows:

a. Exits to stairtowers, or stairways which lead directlyto adequately sized qualified refuge areas. At leastone stairtower must serve each MVZ. Where multiple deckpublic spaces are served by such stairtowers, the stairtread width limits egress flow. See paragraphs 17, and23-26 regarding the sizing of egress components formultiple-deck spaces. Stairways that are wholly withina balcony or atrium, providing access within that space,are not considered to contribute to the required meansof egress.

b. Exits opening directly to weathex decks where acontinuous egress path to qualified refuge areas isprovided, or

c. Exits through an MVZ bulkhead that directly access anadequately sized, adjacent public space which is aqualified refuge area, provided that such exit doors openin the direction of egress. For doors in MVZ bulkheads toreceive credit for service in two directions and takeadvantage of bidirectional swinging doors, they mustprovide direct access to enclosed qualified refuge areas oneach side of the MVZ bulkhead. Practically, these doorsshould be installed in pairs, where one leaf of the pairopens in the direction of egress from one zone, while theother leaf opens in the opposite direction. Each leaf ofthe pair must be provided with its own releasing device.Devices that depend on the release of one door before theother can be released may not be used. The full clear

5

Enclosure (1) to NVIC 8 ._- 93

width of the pair(s) of bidirectional doors may be used indetermining egress capacity. These exits may, however,only receive credit as Stage I Egress components forpersons assumed to be distributed within 22 m (72 ft) ofthe doors. See Figure 1.

[NOTE: The cumulative width of all doors in an MVZ bulkheadon any deck is limited to 25% of the breadth of theMVZ bulkhead on that deck. The intent of thislimitation is to preserve the integrity of the fireboundary while allowing doors in MVZ bulkheads tocontribute to Stage I Egress capacity. If the MVZbulkhead does not lie in one vertical plane, the"breadth" may be measured cumulatively across thetransverse faces of the MVZ bulkhead. Portions ofMVZ bulkheads that form stairtower enclosures shouldbe excluded from this determination.]

15. On vessels having two or more decks, at least one of therequired means of egress from each main vertical zone mustbe a stairtower. A single stairtower may serve two adjacentMVZ's, but need not be sized to accommodate all persons inthe spaces served. It should be assumed that only one spacewill need to be evacuated at a time. The complement of theegress components for each space must be sized toaccommodate the remainder of all those persons who can notbe accommodated by the stairtower. The existingrequirements in 46 CFR 72.10, regarding "two means ofescape" apply. Elevators may not be considered as one ofthe required means of egress. Notwithstanding theprovisions of 46 CFR 72.10-20(a), lockable doors which leadto weather must be designed such that they can be easily andreadily opened from the inside.

16. While it is preferable to locate refuge areas as close aspracticable to the embarkation deck, this is not alwayspossible, some vessel designs provide qualified refuge areason the uppermost exposed decks. Stairtowers must extend tothese and other decks where qualified refuge is provided,even if these decks are not normally accessible topassengers. Uppermost decks that are accessible topassengers, even if not refuge areas, must have directaccess to a stairtower.

MULTIPLE-DECK SPACES

17. Multiple-deck spaces present unique challenges with respectto egress since a fire originating on any level of the spaceimpacts the safety of persons on all levels, thusnecessitating simultaneous evacuation of the entiremultilevel space. To this end:

a. The design of the egress system must ensure thatsimultaneous evacuation of all levels of the space does

6

Enclosure (1) to NVIC 8 - 93

not delay the egress of occupants due to overloading ofstairways. Therefore, stairtowers and stairways(including exterior stairways) may only receive "credit"for the number of persons for which they are designed.For example, assume that the doors and stair tread widthof a stairtower serving a three-deck atrium are sized toaccommodate 200 persons. In this case, a total of 200persons may be assumed to exit the atrium via thisstairtower - not 200 persons from each level of theatrium. The 200 persons assumed to exit the atrium viathis stairtower should be proportionately distributedamong the various levels based on the ratio of thenumber of persons assumed to normally occupy each level,to the total number of persons assumed to occupy theatrium. The remaining persons in the multiple-deckspace must use other Stage I Egress components. Seeparagraph 26 for sizing.

b. Public spaces encompassing two decks, such as balconyarrangements, must be protected by an automaticsprinkler system. The deck opening in both balconiesand atriums should be substantial, such that occupantson each level have a sense that both decks belong to thesame space for reasons of fire safety. The NationalFire Protection Association (NFPA) Life Safety Codesuggests that the minimum dimension of the openingshould be not less than 6 m (20 ft) across with an areaof not less than 93 m (1000 ft 2

). Since this may not bepractical for smaller vessels, deck openings, on allvessels, should be sized to be not less than 20% of thefull deck area without the opening (within the enclosedpublic space). Where it is not practical to have deckopenings this large, such openings shall be protectedaround the perimeter by automatic sprinklers and draftstops as indicated in NFPA 13, Chapter 4, paragraph4.4.1.7.3.4. Briefly, this requires a draft stopextending down below the ceiling into the lower space 46cm (18 in) deep surrounding the opening and automaticsprinklers fitted at not more than 1.8 m (6 ft)intervals around the perimeter.

c. Except as described above, deck to deck integrity mustbe maintained. Public spaces that contain openings inthe bulkhead deck will require special consideration.

STAGE II EGRESS - EGRESS FROM QUALIFIED REFUGE AREAS TOEMBARKATION AREAS

18. Means of egress protected from potential fire impacted areasmust be provided from qualified refuge areas to theembarkation area (port and starboard). These means ofegress are referred to as Stage II Egress routes. A numberof options are available to provide the requisite level ofprotection for Stage II Egress routes leading from refuge to

7

Enclosure (1) to NVIC 8 _. 93

embarkation areas. No special Stage II Egress protection isrequired on a vessel which has: multiple MVZ's, providesout-of-zone qualified refuge area (QRA) for all persons onboard after evacuation of the fire affected MVZ, andprovides access to the embarkation area from within eachMVZ. The following arrangements are also consideredacceptable:

a. Type 1 stairtowers which can be accessed directly fromthe qualified refuge areas; or

b. Routes via non-affected qualified refuge areas leadingto port and starboard embarkation areas which can bedirectly accessed from the qualified refuge areas beingconsidered.

19. The embarkation area i.s considered to be on the deck fromwhich passengers board primary lifesaving equipment. Ifpassengers are not lowered to the water in survival craftvia davits or launching devices, the embarkation deck shouldbe the deck closest to the water, generally no more than2.0 m (6.5 ft) above the waterline, to allow the safestaccess for passengers to reach lifesaving equipment, rescuevessels, or the shore, from the vessel.

20. Title 46 CFR 72.05-20(s)(3) requires that each Type 1stairway or stairtower provide at least 112 cm (44 in) ofexit door width to each side of the vessel on theembarkation deck, either directly to weather, or indirectlyby passageways and/or corridors which lead to weather. TheCommanding Officer, Marine Safety Center may acceptalternative arrangements considered to provide an equivalentlevel of safety to this requirement. Specifically,stairtower arrangements may be accepted which provide accessto only one side of the vessel on the embarkation deck,provided that the design includes adequate and redundantmeans of egress for persons in qualified refuge areas togain access to embarkation areas on the opposite side of thevessel. At least one of these means of egress must meet theprotection requirements for Stage II Egress routes describedin this enclosure.

21. There must be at least two means of egress provided from thevessel to the pier or dock for vessels which have passengerson board while moored.

ALTERNATIVE STAIRTOWER ARRANGEMENTS

22. Many vessels to which this NVIC may be applied incorporate agalley and/or other spaces where a fire may originate belowdecks. Taken together, the requirements of 46 CFR 72.0520(e) and 72.05-20(f) may be difficult to satisfy on certainvessels. Essentially, the former requires stairtowers toextend to all decks, and the latter discourages designs

8

Enclosure (I) to NVIC8 -- 93

where stairtowers provide direct access to accommodations orother enclosed spaces in which a fire may originate. Whereit is impractical to comply with 72.05-20(f), and in orderto improve the safety of such arrangements while permittingdesign flexibility, the Commanding Officer, Marine SafetyCenter may accept stairtower arrangements determined toprovide an equivalent level of safety to designs meetingregulatory standards. Specifically, stairtowers which donot extend to below-deck spaces may be accepted, if thesespaces are provided with adequate (stairway) means of egressdirectly to a weather deck. Persons exiting the below deckspace to weather must be provided access to an embarkationarea as well as access to either a stairtower or qualifiedrefuge area, without entering a fire affected space.Alternatively, the Commanding Officer, Marine Safety Center,may also accept other arrangements which include selfclosing fire doors at both the top and bottom of a stairwayleading from the below-deck space to a stairtower enclosure,giving due consideration where the below-deck space(s) isprotected by an appropriate fixed fire suppression system.

SIZING OF EGRESS COMPONENTS

23. The requirements for stairtower landing areas in 46 CFR72.05-20(r)(2) need not be applied. Landings for allstairways (including stairtowers) must meet the requirementsof 46 CFR 72.05-20(r)(1) and (3).

24. The minimum tread width of interior and exterior stairwaysand stairtowers is determined by multiplying the number ofpersons to be served by that stairway or stairtower by0.846 em/person (0.333 in/person). The tread width ofrequired stairtowers may not be less than 112 em (44 in).The tread width for other stairways may not be less than92 em (36 in), unless the stairway is for crew use only, inwhich case the clear width may not be less than 72 em (28in). The number of persons who will be using the stairwaysand stairtowers must be determined for the spaces served ona deck-by-deck basis using the guidelines provided in theabove section titled "Determination of Maximum Number ofPersons Permitted." On any particular deck, only thosepersons in areas assigned to use a stair are involved in thewidth determination. However, once a minimum required widthhas been established at anyone level, that width may not bereduced at any subsequent deck level in the direction ofStage I Egress.

[NOTE: The Commanding Officer, Marine Safety Center, may approvestairway widths less than 0.846 em/person (0.333in/person) served if, based on the arrangement of anyavailable weather deck area (adjacent to exterior stairs)or stairtower landing area, it is demonstrated that useof a narrower stairway will not impede the flow of

9

Enclosure (1) to NVIC B~93

persons out of a space where fire has originated. Inother words, a particular arrangement may provide anexterior stairway or stairtower landing area which is inexcess of minimum requirements. If this excess landingarea is arranged such that persons exiting the deck canreasonably be expected to distribute themselves in thisarea while waiting for the stairway to become clear, thenthe designed capacity of the stairway may be reduced bythe number of persons for which excess landing area isprovided. Such landing areas may be considered to

2 2accommodate one person for every 0.33m (3.5 ft )available. In no case may the stairway width be lessthan the minimum widths noted above.]

25. Other means of egress components, such as doors andpassageways, must be at least 82 cm (32 in) in width or0.846 cm/person (0.333 in/person) multiplied by the numberof people to be served by that egress component, whicheveris greater. All egress components must allow for the easymovement of persons wearing life preservers. There must beno protrusions which could cause injury, ensnare clothing,or damage life preservers. Except as indicated in paragraph14.c above, doors must open in the direction of Stage IEgress from the space and must open clear of the egress pathsuch that flow is not impeded. The number and dimensions ofthe means of egress components for each space must besufficient for the maximum number of persons assumed tooccupy that space as determined using the guidelinesprovided in the section above on "Determination of MaximumNumber of Persons Permitted."

26. If the desired personnel capacity, or the personnel capacityallowed by stability calculations, is less than thatdetermined using the guidelines under "Determination ofMaximum Number of Persons Permitted," the egress componentsmay be sized for the lower capacity. If this is done,however, Coast Guard records will reflect the fact thatmaximum passenger capacity is governed by stabilityconsiderations and/or the sizing of egress components.

SPECIAL FIRE PROTECTION SYSTEMS FOR ATRIUMS

27. An atrium is a public space which spans three or more decks.The guidance in NVIC 16-91, "Special Fire Protection Systemsfor Atriums," applies.

28. NVIC 16-91 requires that the entire MVZ containing an atriumbe protected by a smoke detection system. Since vesselsemploying the alternatives in this NVIC are not permitted tohave overnight passenger accommodations, it is reasonable toexpect that atriums on these vessels will be occupied by alarge number of people whenever passengers are aboard. Eachpassenger and crew member is, in effect, a smoke detector.

10

Enclosure (1) to NVIC 8 ._. 93

Thus, it is not considered necessary that the smokedetection system provide coverage of atria on these vesselsprovided that:

a. All spaces, other than the atrium itself, which pose arisk of fire and which are located within the MVZcontaining the atrium are served by a smoke detectionsystem; and

b. The atrium space is served by an approved manual alarmsystem complying with the requirements of 46 CFR 76.35.If this alternative is employed, manual alarm boxes mustbe located in the vicinity of each exit from the atriumwhich contributes to the required Stage I Egresscapacity.

29. When designing the smoke extraction system required by NVIC16-91, designers should be guided by the standards in NFPA92B, "Smoke Management Systems for Malls, Atria, and LargeAreas." NVIC 16-91 requires that the smoke extractionsystem be activated by the required smoke detection systemand be capable of manual control. For atrium spaces notserved by a smoke detection system (see alternative inpreceding paragraph), the smoke extraction system must beactivated by both the manual alarm system and by water flowin the appropriate zone(s) of the required automaticsprinkler system. The smoke extraction system should bedesigned such that smoke exhausting from the system isunlikely to contaminate Stage I or Stage II Egress routes,refuge areas, embarkation areas, lifeboat/liferaft stowageor lowering stations, and areas where passengers and crewmay need to assemble or occupy in the event of a fire.

PROTECTION OF WINDOWS IN BOUNDARIES ADJACENT TO EXTERIORQUALIFIED REFUGE AREAS OR STAGE II EGRESS ROUTES

30. Window or glazing assemblies adjacent teJ or below "QualifiedWeather Deck Refuge Areas" or "Stage II Egress Routes" needto be rated as fire resistant or otherwise protected tomaintain the intended fire resistance of the boundaries, andmust satisfy one of the following criteria:

[NOTE: When window assemblies are installed in areashorizontally adjacent to external safety areas, thewindows may not extend below a storm rail location,approximately 1 m (35 in) above the deck level.]

a. Glazing assemblies may be used that meet the fireresistance testing standards described in NFPA 251,"Standard Methods of Fire Tests of Building Constructionand Materials," 1990 Edition, Chapters 1-5 and 7; or,Underwriters Laboratories (UL), "Fire Tests of BuildingConstruction and Materials," UL 263, 1984 Edition,Chapters 1-5 and 7 for one hour, including limitation of

11

Enclosure (1) to NVIC 8 ~_. 93

the temperature rise on the unexposed side during thestandard fire test.

b. Glazing assemblies protected by automatic protectionsystems, such as shutter systems or other equivalentmeans, will be considered by Commandant (G-MTH) wherelaboratory testing has been accomplished. Such testingshould be fully documented, including limitations andthe approximate resulting fire resistance rating.Details of such arrangements should include the type ofglazing, thickness, maximum dimensions, framingspecifications and other relevant parameters.

c. Tempered or laminated glass window assemblies of notless than 6.5 mm (1/4 in) thickness meeting no specificfire resistance requirement may be used where: theadjacent enclosed spaces contain a combustible fuelloading of not more than 14.5 kg/m2 (3 Ib/ft2

) and areprotected by an approved automatic sprinkler system,including dedicated automatic sprinklers specificallyarranged and designed to protect such exterior windows.Such window glazings must be held in place by a gasketsystem that permits the glass framing system to deflectwithout breaking (loading) the glass before thesprinklers operate, and fitted with steel clips toprevent glazings from falling out where window framingmaterials are heat sensitive or do not otherwise keepintact glazings from falling out under fire conditions.Automatic sprinkler systems using this provision forwindow protection must be designed and installed inaccordance with NVIC 10-93, "Guide to the Acceptance ofNational Fire Protection Association Code No. 13 forAutomatic Sprinkler System Design, Installation andMaintenance." Window assemblies containing wireinserted glass may be treated similarly.

Alternative arrangements of protecting glazing assembliesthat are shown by fire testing to provide effective fireresistance will be considered by Commandant (G-MTH-4) on acase-by-case basis. Such testing may show different glazingdimensions can be used, if different water flow rates areeffective, or alternative window glazing and/or framingmaterials result in an equivalent barrier.

31. Where windows are installed in doors, or in sidelightsadjacent to doors, they may be subject to human impact.Such windows or glazings should meet the impact requirementsof American National Standards Institute (ANSI) Z97.1-1984,Standards for Architectural Safety Glazing Materials and/orConsumer Products Safety Standard 16 CFR 1201 "SafetyStandard for Architectural Glazing Materials."

12

Enclosure (1) to NVIC B'- 93

DOCUMENTATION OF COMBUSTIBLE FIRE LOAD

32. For new construction, calculations and documentation must besubmitted to the Marine Safety Center for review of thecombustible fire load. The fire loads must not be increasedover time for each space required by this NVIC to maintain acombustible fire load of not more than 14.5 kg/m2 (3lb/ft2

).

Whenever internal furnishings are altered such that the fireload within the space may have increased, the vessel ownermust submit calculations and documentation to demonstratethat the fuel loading of the space remains below theallowable limit.

ELEVATORS

33. Elevators should be designed using the guidelines providedin G-MTH Policy File Memorandum 1-93. Elevators constructedto American National Standards Institute/American Society ofMechanical Engineers (ANSI/ASME) A17.l are consideredacceptable.

DRAFT STOPS

34. Draft stops (46 CFR 72.05-l0(h» are not requiredabove/around large public spaces provided all of thefollowing conditions are met:

a. The space in question is surrounded by A-Class divisionsor extends to the outer shell of the vessel.

b. The space in question is open and unobstructed such thata fire in any part of the space will quickly bediscovered.

c. The area above the ceiling is easily accessible frombelow for fire fighting purposes.

d. Combustibles in the space above the ceiling are limitedto electrical cable for lighting circuits.

EMERGENCY EVACUATION PLAN (EEP)

35. The crew provides an essential service in time of emergency.The Emergency Evacuation Plan (EEP) provides information tothe master and crew regarding procedures they must carry outin the event of a shipboard fire. The EEP should generallybe in the form of a pamphlet providing a written descriptionof the various safety features and emergency procedures. Inaddition, the EEP should contain simplified diagrams of thevessel's emergency egress and refuge systems, anddescriptions of fire protection equipment. Each member ofthe crew should be required to become familiar with these

13

Enclosure (1) to NVIC 8-93

systems so they can direct passengers to safe refuge areasin an emergency and take appropriate action to contain andcombat the fire. When conducting drills during inspectionsfor certification and reinspections, Coast Guard MarineInspectors will query the crew on the content of the EEP toensure they are familiar with the egress and refuge systems.

36. The EEP must be submitted to the Marine Safety Center forreview along with detailed plans which:

a. Identify the number of persons (passengers and crew)assumed in each enclosed space and weather deck area andhow the number was determined;

b. Identify possible fire scenarios (including fire in thelargest capacity passenger space in each MVZ) anddescribe the flow of passengers and crew to qualifiedrefuge areas (Stage I Egress routes), for eachsituation;

c. Show egress component dimensions and capacities;

d. Identify and describe the characteristics and capacitiesof qualified refuge area(s) where passengers will musterin the event of a fire;

e. Identify the embarkation areas and show how passengerswould be evacuated to them from qualified refuge areas(Stage II Egress routes), and then from the vessel(develop a plan for abandoning ship);

f. Describe how passengers will be informed, prior tovessel departure, and during an actual emergency, of theemergency procedures and what they are expected to do inthe event of fire; and

g. Provide any other information necessary to document thefire protection systems, structural fire protection,ventilation system, and egress system design.

14

t-'Ul

TABLE 1: STANDARDS FOR INTERNAL QUALIFIED REFUGE AREAS

VESSELS WITH ONE MVZ ANDMULTIPLE-MVZ VESSELS WHICH PROVIDE QUALIFIED MULTIPLE MVZ VESSELS WHICH DO NOT PROVIDE QUALIFIED

FIRE SAFETY FEATURE REFUGE AREA FOR ALL PERSONS ON BOARD AFTER REFUGE AREA FOR ALL PERSONS ON BOARD AFTEREVACUATION OF THE HIGHEST CAPACITY MVZ EVACUATION OF THE HIGHEST CAPACITY MVZ

TYPE I LOCATION OF SPACE Public spaces· located above the bulkhead deck Public spaces. located above the bulkhead deck.which are not within the fire affected MVZ.

STRUCTURAL FIRE PROTECTION MVZ boundaries must be insulated to A-60. The space must be bounded by A-60 bulkheads andOF BULKHEAbS AND DECKS decks, except that bulkheads and decks adjacent to

weather and other low fire risk spaces (such asvoids, cofferdams, tanks, etc.) may be A-O unlessa higher standard is otherwise required bySubchapter H.

VENTILATION SYSTEMS May not serve more than one MVZ. May not serve more than one MVZ. Within an MVZ,ventilation systems serving the qualified refugespace must be completely independent of any otherspace ~ be separated from other spaces within theMVZ by smoke and fire dampers. Dampers meeting therequirements of 46 CFR 72.05-50(b) and (e) andUnderwriters Laboratories, Inc. "Standard forLeakage Rated Dampers for Use in Smoke ControlSystems" (UL 555s) are considered acceptable.

FIRE SUPPRESSION SYSTEMS Except as provided below, spaces which share common boundaries with the qualified refuge area andwhich pose 8 risk of fire (such as accommodation, service and machinery spaces) must be protected byan appropriate fixed automatic fire suppression system.

Accommodation spacZs with fi~e loads less than or No exceptions.equal to 14.5 kg/m (3 1b/ft ) which share commonboundaries with qualified refuge areas need not beprotected by a fixed automatic fire suppressionsystem if veneers and trims used in the qualifiedrefuge areas are incombustible.

* The meaning of the term "public space" used in this Table means a public 8pace as defined in 46 CFR 72.05-5(b)(1).

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......

'"

TABLE 2: STANDARDS FOR WEATHER DECK QUALIFIED REFUGE AREAS

VESSELS WITH ONE MVZ ANDMULTIPLE-MVZ VESSELS WHICH PROVIDE QUALIFIED MULTIPLE MVZ VESSELS WHICH DO NOT PROVIDE QUALIFIED

FIRE SAFETY FEATURE REFUGE AREA FOR ALL PERSONS ON BOARD AFTER REFUGE AREA FOR ALL PERSONS ON BOARD AFTEREVACUATION OF THE HIGHEST CAPACITY MVZ EVACUATION OF THE HIGHEST CAPACITY MVZ

LOCATION Weather decks not within the fire affected MVZ. Any weather deck area.

FIRE SUPPRESSION SYSTEMS No special requirements beyond Subchapter H. Spaces which share common boundaries with thequalified refuge area and which pose a risk of fire(such as accommodation, service and machineryspaces) must be protected by an appropriate fixedautomatic suppression system.

STRUCTURAL FIRE PROTECTION No special requirements beyond Subchapter H. The deck (except areas in way of overhangs, fuel,OF DECKS AND BULKHEADS water, ballast tanks, and voids, etc. ), must be

insulated to A-60. Adjacent bulkheads must beinsulated to 46 CFR Table 72.05-10(e), standardsapplicable to "Lifeboat embarkation or loweringstations."

WINDOWS AND AIR PORTS No special requirements beyond Subchapter H. Must receive special treatment. See paragraph30 of this enclosure.

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......

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Enclosure (2) to NVIC R_. 9 .:~,.; ,,)

Equivalent Alternatives to 46 CFR 72.05 Requirements forLimitation of the Mean Length of Main Vertical Zones

GENERAL

1. These policies have been developed as a result of publicinterest. In early 1992, the Coast Guard was presented withtwo conceptual proposals under the provisions for equivalentsin 46 CFR Parts 70 and 72 for riverboat gaming vessels whichincorporated main vertical zones (MVZ's) much longer thanpermitted by 46 CFR Subchapter H, but which offered numerousother compensating fire safety features not required bycurrent regulations. On April 1, 1992, the Coast Guardpublished a Federal Register Notice inviting interestedmembers of the public to submit comments and proposals foralternative standards which would provide an equivalent levelof safety to existing requirements and policies which limitMVZ length to a maximum of approximately 40 m. All but oneof the 18 respondents favored relaxation or elimination ofMVZ length limitations, with incorporation of additional firesafety requirements. Recognizing that limitation of MVZlength is a time-proven, internationally recognized standardfor shipboard fire protection, the Coast Guard proceededcautiously in developing alternative MVZ design andperformance standards to ensure that they provide a level ofsafety commensurate with the unique risks associated with thecarriage of many passengers on limited service vessels havingno overnight passenger accommodations. The approach in thisenclosure reflects this balance.

2. Vessels which comply with the guidelines in this enclosuremay incorporate MVZ's which exceed 40 m in length, to theextent described herein.

3. Unless indicated otherwise, these guidelines must be appliedin addition to those contained in enclosure (1) of this NVIC.

4. Fire safety areas which are impacted by increasing thelongitudinal distance between passive fire barriers arediscussed below. For simplicity, an MVZ having a length thatexceeds 40 m will be referred to as a "long MVZ" or "LMVZ" inthis enclosure.

a. Human Factors and Systems Safety. The potential forconfusion and panic during emergency egress may increasewith increased occupant loading of a space. This hazardcan be mitigated by detecting fire early, controlling it,and extinguishing it at the incipient stage. Further,

Enclosure (2) to NVIC 8 ~= 93

the behavior of occupants can be favorably influencedthrough the proper design and marking of the egresssystem to facilitate the orderly flow of occupants toprotected refuge areas, use of passenger safetybriefings, and improved control capability for notifyingaffected passengers of emergency situations. The lattercan be accomplished via control station alarms thatindicate activation of smoke detection and automaticsprinkler systems, coupled with targeted emergencyannouncements which can assist in the control ofpassenger movement. In addition, the potential forpassenger entrapment due to overcrowding at exits can bereduced by installing "panic hardware" on doors whichenable them to be opened under these conditions.

b. Smoke Detection and Alarms. The control of fire andsmoke can be improved via early smoke detection and/ormanual pull station alarms which alarm at a continuouslymanned control station. These systems provide criticalearly notification to persons in charge, which reducescrew response time and the start of passenger evacuation.

c. Fire SUQQ±ession Systems. To control a fire at anincipient stage, an automatic sprinkler system isrequired in all accommodation and service spaces onvessels incorporating LMVZ's. These systems are quick,automatic, and reliable when properly designed andmaintained. The Coast Guard considers their useessential to control fire early and compensate for theincreased size of a fire affected area associated withLMVZ's. The use of Quick Response (QR) sprinkler headsis also required. These QR sprinkler heads represent anegligible cost increase and react faster when comparedto conventional sprinkler heads. Because of this, QRsprinklers typically control fires with fewer heads thando conventional sprinkler systems for the types of spacesconsidered herein. Up-to-date guidance on the marineapplication of National Fire Protection Association(NFPA) Code No. 13 for design and installation ofautomatic sprinkler systems will be published through aseparate NVIC. Fixed fire suppression systems are alsorequired in machinery spaces.

d. Eg~~ss System. Under existing regulations, the maximumdistance between exits from a space is not specified. Inaddition to the "two means of escape requirement,"stairtower spacing is linked to MVZ length which is setat 40 m (131 ft). In certain cases, Commandant haspermitted longer MVZ's, but generally limited theextension to no more than 10% over the existing 40 m (131ft) limitation. Thus, to ensure that passengers and creware provided with readily accessible internal means ofegress from LMVZ's, this enclosure specifies a maximumlongitudinal distance between Type 1 stairtowers.

2

a q ,-.Enclosure (2) to NVIC _ - , ~)

Similarly, since this NVIC permits the balance of egresscapacity to be provided through stairways which leaddirectly to qualified refuge, direct exit doors toweather decks and/or to qualified refuge areas via MVZbulkhead doors, the maximum horizontal distance from anypoint in an LMVZ to an exit forming part of a Stage IEgress route is specified. The sizing of door widths andstairs is dependent on the number of persons served, andis not a function of MVZ spacing. Thus, the guidance inenclosure (1) for determining minimum door and stairtread widths is also applicable to vessels having LMVZ's.

e. Directly Accessible Qualified Refuge Area (QRA) and ExitDischarge Area (EDA). Due to the difficulties that maybe encountered when evacuating larger numbers of peopleto refuge areas, greater attention must be paid tokeeping Stage I Egress routes simple. To this end,qualified refuge areas and/or exit discharge areas mustbe directly accessed from a public space through "simplemodes," as described in paragraph 14 of enclosure (1).Where QRA's cannot be directly accessed throughstairways/stairtowers or through MVZ bulkhead doors, exitdischarge areas must be provided in weather deck areasimmediately outside, and on the same level of the publicspace to be evacuated. In this way, circuitous egressroutes that could potentially restrict passenger egressare avoided. The QRA's and EDA's directly accessed mustbe sufficiently sized and matched to the doors servingthem. See Figures 1 and 2.

f. Fire Containment and Control. By itself, an increasedspacing between fire barriers on vessels incorporatinglonger MVZ's reduces the degree of fire and smokecontainment. However, the lesser degree of firecontainment permitted can be adequately compensated forwith appropriate control, suppression, and refugemeasures and by reducing the rate of fire growth throughfuel limitation. This enclosure maintains the limitationon the combustible fuel load throughout all accommodationspaces in LMVZ's to a maximum of 14.5 kg/m2 (3 Ibs/ft

2)

established in NVIC 14-91. Even when these additionalsafety features are included, fire barriers must still beincorporated in a vessel's fire protection design so thategress routes and refuge areas can be adequatelyseparated from a fire affected space.

REQUIREMENTS

DETERMINATION OF MAXIMUM NUMBER OF PERSONS PERMITTED

5. The guidance contained in enclosure (1) applies.

3

Enclosure (2) to NVIC

STAGE I EGRESS - EVACUATION OF THE SPACE OF FIRE ORIGIN ANDMOVEMENT TO QUALIFIED REFUGE AREAS

6. The guidance contained in enclosure (1) regarding "Stage IEgress" applies except as modified in this section.

7. Distance to Exits. The maximum longitudinal distance betweenType 1 stairtowers and distance from any point within theLMVZ's may not exceed 40 m (131 ft). The maximum horizontaldistance from any point in an LMVZ to an exit door formingpart of a Stage I Egress route may not exceed 22 m (72 ft).

8. Panic or Fire Exit Hardware. All doors which contribute tothe required egress capacity for large public spaces locatedwithin LMVZ's must be equipped with panic or fire exithardware. Fire exit hardware consists of a door latchingassembly incorporating a device that releases the latch uponapplication of a force in the direction of exit travel. Suchdevices should:

a. Consist of bars or panels, the actuating portion of whichextends across not less than one-half of the width of thedoor leaf, and not less than 76 em (30 in) nor more than112 em (44 in) above the deck; and

b. Cause the door latch to release when a force not toexceed 65 N (15 Ibf) is applied.

[NOTE: Where panic or fire exit hardware is fitted to firerated doors or doors constructed to meet 46 CFR72.05-25(b), the submission of fire door detailsshould include information on the panic or fire exithardware such as construction materials, dimensions,latch throw, and listing. Questions regarding firedoor construction or testing requirements applicableto "fire rated doors" may be addressed to Commandant(G-MVI-3).]

9. Exit Discharge Area (EDA). Paragraph 14 of enclosure (1)applies as modified herein. For LMVZ's, "simple modes ofaccess" must open directly to qualified refuge areas and/orexit discharge areas. The requirement that protected QRA beprovided for 100% of persons on board is not affected by EDA.This requirement specifically modifies paragraph 14.b ofenclosure (1) where evacuation of the space includes directegress to weather decks. For the purposes of this enclosure,an exit discharge area is defined as weather deck arealocated immediately outside of, and adjacent to exit doorsfrom a large public space. The purpose of specifying minimumexit discharge area (EDA) is to ensure that occupants of alarge public space can rapidly evacuate to available spaceduring the initial surge of crowd movement in an emergency.Exit discharge areas must provide sufficient deck area

4

Enclosure (2) to NVIC 8-93

immediately outside of an affected public space where aninsufficient QRA is available via stairtowers/stairways orhorizontally through fire doors in MVZ bulkheads.Specifically:

a. From an exit door, the EDA must lead in the direction ofStage I Egress to the QRA;

b. The EDA must provide area of not less than 0.33 m2 (3.5ft 2

) per person for people using the corresponding exitdoor;

c. The EDAs should not overlap, such that the allocated areafor persons flowing from a given exit door into theirrespective EDA is not impeded by the flow of personsevacuating from other exit doors; and

d. The EDA width must not be less than the exit door widthwhere one Stage I Egress route (direction) is available,and not be less than 1/2 the exit door width where twoStage I Egress routes are provided immediately uponpassage through the corresponding exit door. In no caseshould the EDA width be less than 1 m (39 in).

10. Matching Exit Widths to available EDA. The available exitdischarge area (EDA) should be considered when sizing exitdoors to weather to ensure that the Egress system and EDAcomponents are reasonably well matched. A simplifiedexample is depicted in Figure 2. Assume that the doorlabeled "A" is sized to accommodate 100 persons. To fullyutilize the egress capacity of this door, the exit dischargearea (shown shaded in the figure) must have a clear deck

2 2area of at least 0.33 m /person x 100 persons = 33 m toaccommodate the 100 persons assumed to exit door "A" in anemergency. If less exit discharge area is provided, thenumber of persons assumed to exit this door must be limitedaccordingly.

QUALIFIED REFUGE AREAS

11. Location of Qualified Refuge Areas. Controlling themovement of many hundreds of passengers and crew in anemergency situation is critical to the safe evacuation of alarge public space. To simplify passenger movement andfacilitate rapid evacuation of a fire affected space locatedwithin an LMVZ, it is recommended that, to the greatestextent possible, qualified refuge areas be provided out ofthe affected LMVZ for each deck level to accommodate allpersons assumed to normally occupy that deck. Thepercentage of persons required to be provided with "out-ofzone refuge" increases with increasing LMVZ length, as shownin Figure 3.

5


12. Protection of Qualified Refuge Areas. The requirements ofenclosure (1) apply. See Tables 1 and 2. In addition,windows installed in exterior bulkheads that face out-ofzone weather deck QRA must be protected by an exteriorsprinkler water wash system. Such systems shall beinstalled in accordance with NVIC 10-93 "Guide to theAcceptance of NFPA 13 for Automatic Sprinkler Design,Installation and Maintenance."

STAGE II EGRESS - FROM QUALIFIED REFUGE AREA TO EMBARKATION DECKS

13. The alternative stairtower arrangements permitted inenclosure (1) may be incorporated in vessels having LMVZ's,subject to the following restriction. If a stairtowerprovides access to the embarkation deck on only one side ofthe vessel within an LMVZ, at least one other stairtower inthat LMVZ must provide access to the embarkation deck on theopposite side of the vessel.

SIZING OF EGRESS COMPONENTS

14. The guidance contained in enclosure (1) applies.

LIMITATION OF COMBUSTIBLE LOAD

15. The combustible fire load contained in public spaces which2 2lie within LMVZ's may not exceed 14.5 kg/m (3 lbs/ft ).

SMOKE DETECTION AND ALARM SYSTEMS

16. Public spaces of 465 m2 (5000 ft 2) or more which are Dot

served by a Coast Guard approved smoke detection system mustbe served by an approved manual fire alarm system complyingwith the requirements of 46 CFR 76.35. Spaces other thanpublic spaces of 465 m2 (5000 ft 2

) or more, which arelocated within an LMVZ and which present a risk of fire mustbe served by a Coast Guard approved smoke detection system.In large public spaces where a manual alarm system isrequired, alarm boxes must be located in the vicinity ofeach exit that contributes to the required Stage I Egresscapacity.

MULTIPLE-DECK SPACES

17. The guidance in enclosure (1) applies.

SPECIAL FIRE PROTECTION SYSTEMS FOR ATRIUMS

18. The guidance in enclosure (1) applies.

6

Enclosure (2) to NVIC 8 - 9:3

FIRE SUPPRESSION SYSTEMS

19. Each accommodation and service space throughout the vesselmust be protected by a supervised, automatic sprinklersystem equipped with quick response (QR) sprinkler heads.Two sprinkler pumps are required. Each must be able toprovide the required pressure for the sprinkler system.

LIMITATIONS ON MVZ LENGTH

20. There is no absolute limitation on the maximum length of anMVZ above the bulkhead deck. Instead, criteria included inthis enclosure establishes a performance-oriented criteriathat permits design flexibility while providing increasedsafety for greater numbers of passengers and crew as afunction of increasing MVZ length as indicated in Figure 3.The percentage of the persons occupying an LMVZ who must beprovided with out-of-zone (MVZ) qualified refuge areaincreases with increasing LMVZ length. A vessel having anLMVZ, the mean length of which is less than 61 m (200 ft),may provide in-zone qualified refuge areas for 100% of thepersons assumed to occupy that zone. A vessel having anLMVZ, the mean length of which is 61 m (200 ft) or greater,must provide out-of-zone qualified refuge areas for thepercentage of persons indicated in Figure 3. The minimumpercentage of occupants for which out-of-zone refuge must beprovided increases linearly from 10% at a zone length of61 m (200 ft), to 100% at a zone length of 110 m (360 ft) ormore. Out-of-zone refuge areas may be internal and/orweather deck qualified refuge areas. Windows facingalternate zone weather deck refuge areas must be protectedas indicated in paragraph 12, above.

21. Below the main bulkhead deck, regulatory limitations on thelength of fire zones remain applicable since damagestability requirements and subdivision requirements willusually dictate additional watertight bulkheads. Sincegreater spacing is permitted between fire zones above themain deck, some intermediately spaced fire zone bulkheadslocated below the main deck will not align with mainvertical zone bulkheads. However, the existence of thesenon-MVZ fire barriers below the main deck reduces theexposure to spaces above the main deck from a fire belowdecks. Each below deck fire zone must be served by a Type 1stairtower or satisfy one of the alternative acceptablestairtower arrangements provided for in enclosure (1) ofthis NVIC.

AUTOMATIC EMERGENCY VOICE ALARM AND DIRECTIONS SYSTEM Acv~ps

22. An Automatic Emergency Voice Alarm and Directions System(AEVADS) must serve each vessel which incorporates an LMVZ.The AEVADS must be capable of transmitting real time,prerecorded intelligible speech messages above the highnoise levels encountered under emergency conditions

7


throughout all public spaces and any other spaces which arenormally manned. AEVADS must be reviewed by Commandant,U.S. Coast Guard (G-MTH-2). Listing or classification by aNationally Recognized Testing Laboratory to a AEVADSstandard, recognized by the Commandant, may be considered asequivalent. Type approved fire or smoke alarm systems whichincorporate AEVADS must be shown to not degradate theoperation or performance of the alarm system. Except whereindicated below, design and installation must comply with 46CFR Subchapter J, Parts 110-113 and the National ElectricalCode, and be designed to meet the following parameters:

a. Upon activation of the AEVADS, the alarm sequence shouldcommence with the sounding of the General Alarm for 3 to10 seconds, followed by AEVADS prerecorded messages.This sequence is to be repeated continuously untileither the system is manually overridden orintentionally terminated at the central control station.

b. The minimum sound level required for the system shallconform to Title 46 CFR Subpart 113.50, and Table113.50-15. Harmonic distortion shall not exceed 5% witha flat sound output response + 6 dB for frequencies from500 - 5,000 Hz. The system shall be operable within 10seconds after turning on power.

c. AEVADS may use components of existing shipboardannouncing or entertainment systems provided that thesesystems meet the minimum requirements of this section.Upon activation of the AEVADS, all announcing systems orentertainment systems on line must be automaticallydisconnected. The system shall contain dual amplifiersand be arranged for quick shift over at the centralcontrol station. If the AEVADS is installed independentof a required Emergency Loudspeaker System (46 CFR113.50), the installation may be made in accordance withNFPA 72, with placement of loudsp~akers in accordancewith 46 CFR 113.50-15. If loudspeakers are independent,use of loudspeakers should temporarily interrupt theautomatic message. The loudspeaker system shall havethe capability of selecting which zone(s) the manualvoice message will be transmitted.

d. The system shall be designed to withstand the corrosive,humid, and vibratory environment aboard ship. Thesystem must meet the survivability standards in NFPASection 72, Chapter 10-3. The AEVADS must be fittedwith a ground detection system capable of selectivelymonitoring individual zones. Any occurrence of an open,ground or short circuit fault in any zone shall notimpact the operation of the system for any other zone;and shall not reduce the output of any other loudspeakerby more than 3 dB. A visual and audible trouble alarm

8

.'

(<Enclosure (2) to NVIC d

to indicate a fault in any zone is to be mounted at acentral control station.

e. The power supply for the AEVADS must be supplied from adedicated branch circuit from the emergency switchboardwith a backup of battery supply or a final emergencypower source as required by 46 CFR 112.05-5 and 46 CFR112.15-1(j). The dedicated circuit on the emergencyswitchboard must be clearly marked in red: "EmergencyVoice Alarm Circuit Control."

f. The records required by NFPA 72, Chapter 10-2.4, must bekept aboard the vessel and made available to the CoastGuard upon request. The vessel operator shall conductmonthly operational tests of all equipment and maintaina log of all test dates and test reports. OCMIs shouldrequire that proper operation of the AEVADS bedemonstrated in random spaces served by the systemduring reinspections. OCMIs should witness a completetest of the AEVADS at least annually.

g. The operator at the central control station shall have alockout key capability to override the AEVADS in theevent:

(1) Confirmation is received from vessel crew that thealarm is false;

(2) It becomes necessary to switch to throughout-vesselannouncement; or

(3) Manual emergency announcement for a situation otherthan fire is required.

h. The AEVADS should have a customized message for eachlarge passenger space. The system shall have thecapability of simultaneously delivering one message to afire affected space(s) and another message to all othermanned spaces.

i. The AEVADS shall be activated by manual pull stations,by alarming of the fire detection system, or sprinklerflow. A single detector alarm is not to trigger theAEVADS. A 60 second time delay is to be fitted withinthe system to allow direct phone checks and verificationof fire by ship's staff. The delay should not to befitted to manual pull station signals.

j. The text of each message shall be provided to thecognizant OCMI evaluating the EEP to verify the accuracyand appropriateness of messages. The message deliveredto the space(s) of fire origin should be as simply

9


stated as possible. Consideration should be given tothe inclusion of the following information:

(1) Designation of area affected;

(2) Instructions to exit the space of fire origin; and

(3) Direction to passengers to follow the instructionsof the crew after exiting the space of fire origin.

EMERGENCY EVACUATION PLAN (EEP)

23. In addition to the information required by enclosure (1),the EEP and supporting plans must include appropriateinformation necessary to document the additional designfeatures and safety systems required for vesselsincorporating LMVZ's.

10

".

Figure 1:DIRECT ACCESS TO QUALIFIED REFUGE AREA (QRA)THROUGH MAIN VERTICAL ZONE BULKHEAD DOORS

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ALTERNATE ZONE REFUGE CAPACITY

Enclosure (2) to NVIC 8-9~

MAXIMUM ZONE LENGTHVS.

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MAXIMUM LENGTH OF LONGEST LMVZ (METERS)

Figure 3: Out-of-Zone Refuge Requirements13


Definitions of Terms Used in Enclosures 1 and 2

1. Passenger capacity - number of passengers permitted on avessel. This is limited either by sizing of egresscomponents and refuge areas, or stability of the vessel.

2. Means of egress - route of travel from passenger spaces toqualified refuge areas and embarkation decks.

3. Qualified refuge areas - spaces which are designated as areaswhere passengers go in an emergency. They must be properlysized, protectively bounded from fire and smoke, and provideprotected access to the embarkation area.

4. Fire and smoke control and containment - keeping fire andsmoke to the compartment of origin.

5. Fire suppression - control and/or extinguishment of a fire.

6. Egress components - components of egress routes (i.e.,stairtowers, stairways, landing areas, doors, corridors,etc. ) .

7. Egress capacity - the total number of persons the aggregateof all the egress components in a single space canaccommodate.

8. Embarkation area/deck - the deck from which passengers boardprimary lifesaving equipment. If passengers are not loweredto the water in survival craft via davits or launchingdevices, the embarkation deck should be the deck closest tothe water, generally no more than 2.0 m (6.5 ft) above thewaterline, to allow the safest access for passengers to reachlifesaving equipment, rescue vessels, or the shore, from thevessel.

9. Stage I Egress - evacuation of the space of fire origin andmovement to qualified refuge areas.

10. Stage II Egress - egress from qualified refuge areas to theembarkation areas.

11. Required means of egress - those egress components necessaryto meet the required egress capacity. These components mustmeet the requirements for sizing and protection delineatedin this NVIC.

12. Main vertical zones (MVZ)- divide a vessel into verticalsections, prevent the rapid spread of fire and smokethroughout the ship, and permit fire fighters time toextinguish the fire. If the fire fighters should fail,

Enclosure (3) to NVIC 8- 93

MVZ's permit passengers and crew time to abandon ship. Themean length between MVZ bulkheads must be no longer than 40m (131 feet).

13. Long main vertical zone (LMVZ) - an MVZ having a length thatexceeds 40 m (131 feet).

14. Balconies - spaces which encompass two decks connected by alarge opening in the overhead of the lower level. Thesecond deck is actually a balcony that runs completelyaround the upper perimeter.

15. Atrium - similar to a balcony space, however the spaceconsists of more than two decks and is covered at the top ofthe series of openings and is used for purposes other thanan enclosed stairway; elevator hoistway; escalator opening;or utility shaft used for plumbing, electrical, airconditioning, or communication facilities.

16. Tread width - the width of the stair along the tread.

17. Smoke detection system - the entire smoke detection systemwhich includes the detectors and the control station alarmsand shall be Coast Guard approved and is subject to therequirements of 46 CFR 76.33.

18. Control station - those spaces in which a continuous watchis maintained and in which radio, navigation, or firecontrol equipment is located.

19. Smoke extraction system - must meet the requirements ofNVIC 16-91 and should be designed such that smoke exhaustingfrom the system is unlikely to contaminate Phase I or PhaseII Egress routes, refuge areas, embarkation areas,lifeboat/liferaft stowage or lowering stations, and areaswhere passengers and crew may need to assemble or occupy inthe event of a fire.

20. Automatic sprinkler system - a sprinkler system whichactivates without the necessity of human intervention and isdesigned in accordance with NVIC 10-93.

21. Fire resistant - a descriptive term applied only toshipboard materials such as fabrics, paddings. anddraperies. It denotes a considerable lower degree of fireprotection than noncombustible, yet maintains a degree ofprotection higher than that of ordinary combustiblematerials used aboard vessels. The intent of specifyingfire-resistant furnishings is to provide materials with alower probability of ignition and flame propagation. Itshould be noted that this term does not, in all cases,denote the identical degree of fire protection used inbuilding construction. Fire resistant furnishings aredefined in 46 CFR 72.05-55.

2


22. Emergency Evacuation Plan (EEP) - The Emergency EvacuationPlan provides information to the master and crew regardingprocedures they must carry out in the event of a shipboardfire. The EEP should generally be in the form of a pamphletproviding a written description of the various safetyfeatures and emergency procedures. In addition, the EEPshould contain simplified diagrams of the vessel's emergencyegress and refuge systems, and descriptions of fireprotection equipment.

23. Public space - spaces such as halls, dining rooms,messrooms, lounges, cafes, and other similar spaces normallyaccessible during the voyage.

24. Exit discharge area (EDA)- weather deck area locatedimmediately outside of, and adjacent to exit doors from alarge public space. The purpose of specifying minimum exitdischarge area (EDA) is to ensure that occupants of a largepublic space can rapidly evacuate to available space duringthe initial surge of crowd movement in an emergency.

25. Panic or fire exit hardware - enable doors to be openedunder overcrowding and panic conditions.

26. Simple modes of access - easy access to a refuge area.Simple modes of access only may have one egress component(i.e., stairtower, stairway, passageway, door (except doorsto and from stairtowers), etc.). This eliminates confusionin an emergency situation.

27. Out-of-zone refuge - An MVZ which provides refuge outsidethe MVZ of fire origin. The refuge area may be internaland/or weather deck space, however it must be outside (foreor aft) the transverse bulkheads which define the LMVZ.

*u.s. G.P.O.:1994-301-717:80468 3

navigation and vessel inspection circular no.8 9'3

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